Hello Ajay Sir..
Thanks again for ur gr8 help for this project.
Sir i had gathered many much information that was provided by you every where on the net.
Well i have some doubts that are to be cleared by .

1) the switch provided in the circuit diagram.
Sir is the switch used here is the on/off switch or the reset switch, please specify.

2)how can i connect real Ac devices such as a bulb,fan,tube etc by replacing the led's.

3)What is the concept of the negative logic used by you in this project and where should be it applied.

4)Most important.
Sir i want to access this project over the world wide web.
hence if my pc is connected to a lan and also to a broadband connection. my pc ip address is 192.168.1.9, and i am able to communicate it on lan, but on the same lan how can i communicate over the internet by a dns server. It would be great help to me if u provide the real time method instead of the name of any website.(dyndns.com)

Well sir please provide me with these details as fast as possible

the above things has been explained many times on forum Please just take a look once..

only thing point i am gonna explain now is #3

Negative Logic means
1 - Off
0 - On

so when you make port pin low, the device connected on that pin turns on.

The reason for choosing -ve logic is when you powerup your board all your controller pins are at logic high so devices connected to controller will be off by default. Thats the basic reason for using -ve logic.

For using haserver over internet you need DNS server (www.dyndns.com)

I thank u Ajay Sir for ur humble support.
Well sir there is a problem, u said that answers to the queries are available in one or another post for home automation, but sir, i have very little time for accesing all the posts so it would be just very thanks to u if u just provide me some answers,

1) the switch provided in the circuit diagram.
Sir is the switch used here is the on/off switch or the reset switch, please specify.

2)how can i connect real Ac devices such as a bulb,fan,tube etc by replacing the led's.

3) sir for connecting on the internet u specified the url dyndns.com, well iregistered my self on that, but every thing that they offer is either charged in dollars or is outof my knowledge. Sir u gave some answers to sunitha of how to connect through the internet, plz provide me with the same details.

I am surely waiting for ur reply, plz answer me sir, as it would take hardly 10 mins to provide me with these details.
Thanks Again
Good Bye

Go through the fol. threads.You'll find all your answers...
http://www.8051projects.net/forum-t183.html
http://www.8051projects.net/forum-t1192.html
http://www.8051projects.net/forum-t5071-30.html

Ajay sir, u have mentioned opto couplers or relay drivers like ULN2003A for switching of relays. well can u plz provide a rough circuit diag for how to connect it.
i.e. MC>>(Optocoupler/ULN)>>RELAY>>220v Device.
Is it possible that we replace only one led with this comonents and all the remaining leds are not disturbed.
Well i have added the transistor 2N3904 and diode , now what kind of load is to applied
Also is there any change to be done in the program code.
Thanks agian, goodbye..

Thanks Sashi for ur humble support, well maybe ajay sir is busy.
Anyways,sashi i would be very thankful to u if u answered my doubts explained in the reply above this.
Also i have completely build the project, nut there are some problems to be taken care of,
1) The circuit some times doesnt react after being connected. i.e. after the connected message displayed if we type the stat command, simply it would be recieved at the haserver prog. but if some delay is done in entering the command then it works fine.

2) the leds are glowing but, all of them are not showing up, if for the first time we switch the tube on by off command then the command gets swaped and the next time we have to make it on by ON command itself

3) on switching the swch led or typing any message two to three leds glowup after successful execution of command.

4) LCD is not working, only lcd backlight glows, no other thing happens

Plz answer my query as my project submission is very near.
Thnaks again. goodbye.

strange problem.. must be something wrong with connections or loose or something..


Command get swapped? what that means?
it looks like something is wrong with your hardware, both problem number 1 and 2 sound strange and normally there is no point, they will occur if data sent and received is correct. Try to check on serial port monitor software if data being sent/received is correct


Again seems a case of faulty hardware...
if you are using updated version of this project then while sending message one LED will glow to indicate new message received.


check contrast first.. otherwise some serious problem with hardware, coz if LCD is not working then your hardware will not work at all.
where as in ur case hardware is working..

Please carefully check your hardware. look for short/loose connections.
make sure you did not burn anything while soldering.

Thanks Again Ajay Sir..
Well i had replaced my LCD with a new one.
Also installed the serial port analyzer. But still the problem described by me continues...
I am showing u a screenshot image of serial port.
Also when i try to write the hex file again in the IC P89c51rd2. It continously displays a message that try to connect using low Buad rate.
Here are the screen shot images..






The LCD that is newly attached now also when switched on displays only the upper Line i.e 1*16 bit line displayed, but the lower line is not displayed. But the LCD backlight works properly.
Plz help Me out.

Sorry for the late reply......
So you're using a P89C51.If I'm not mistaken it's a 6-clock uc as opposed to a standard 12-clock 8051.
So that could be the source of your errors.The HA program was written with a 12-clk cpu in mind.So all timings could go haywire.For eg. serial baud rate for a standard 8051 would be 9600 but the same program in a 6-clk uc would yield a 19200 baudrate.
Dunno how much this would affect the program though.The author,Ajay could answer better...
As for the P89C51's programming error..try with a lower baudrate.If it doesn't work check your serial connection and associated components thoroughly.

Thanks SashiJoseph for ur kind help. Well i would certainly reduce the baud rate but the flash magic software is continously displaying the error specified by in above screenshot image..(2nd image).
So plz help...

Reduce the baudrate in Flashmagic to 4800 or 2400 and see if it programs.....

No, i had checked it and reduced the baud rate upto 2400. Well can u plz give me a circuit daig for the lcd only( i have the one provided for the complete project). i want to make sure that my given connections are correct, as said it only displays the first line with boxes, but the second line remains blank. Plz reply me as fast as possible, as ihav to submit my project in this month. Thanks for ur valuable support.

Well the ckt is already provided with the project.Regardless,here it is........



Plz check all your connections carefully esp the serial link,since you're not able to even program the chip.

Well, i have given my connections same as u provided.....But whats the matter with pin no 15 and 16. i gave 15 as vcc and 16 as ground.(as mentioned for lcd back light). So plz clear the doubt...?

Would be safer to give Vcc to pin 15 through a 100 ohms current limiting resistor.
So your lcd connections are ok.
Write a small code to display sth on both lines of the lcd,program it to your uc and see if it works.

Thanks Ajay Sir.for ur humble support.
I was not available due to my final year eng exams. Well i rechecked the connections and found a missed connectn for lcd. now the lcd is working fine and on connecting the circuit the lcd displays a message. The only problem is that the tube and bulb commands are not working properly. Even on switching on tube the led does not glow up.The swch command is also working properly but on giving on command 4-5 leds glow up. So plz provide me some help according were to look in. Its very urgent for me.

are you able to get messages from server to client and client to server?

I want you to recheck your LED connections (+ve and -ve pins of LEDs)

send me a screenshot of your telnet window..